Visualization of a solar flare and wave of charged particles known as a coronal mass ejection (NASA Solar Dynamics Observatory)

Update, 9:53 p.m.: NASA has responded to questions about its forecast and differences with NOAA. Scroll down to the bottom of this post. Meanwhile, NOAA has produced an excellent video about this event - click here to view.

From 12:31 p.m.: A wave of plasma stoked by an X-class solar flare, the most intense type, is headed towards Earth. This blast of charged particles, known as a coronal mass ejection (CME), is forecast to ignite a geomagnetic storm on Earth over the weekend. NOAA predicts it will be minor, maybe moderate. NASA says it will be moderate to severe.

I ask: which intensity will it be and why aren’t these two science agencies on the same page?

The intensity of the inbound CME matters.

If NOAA’s right, and the ensuing geomagnetic storm is minor, it’s no big deal. It means the high latitudes could be treated to some brilliant auroras over the weekend with few, if any, negative effects on earth-orbiting satellites or the power grid.

On the other hand, if NASA’s right, and the geomagnetic storm is strong to severe, Earth-orbiting satellites could get disoriented and the electrical grid, according to NOAA, could experience “widespread voltage control problems” among other issues. Aurora could be seen as far south as Alabama and northern California.

NOAA and NASA’s predictions about the CME also differ on timing. Last night, NOAA was forecasting a 1 a.m. Saturday arrival of the CME while NASA projected a 6:20 a.m arrival. NOAA has since revised its estimate to 9:00 a.m. NASA tweaked its estimate to 5:17 a.m.

The differences in these predictions raise the question why two government agencies aren’t coordinating and issuing one clear, consistent forecast along with estimates of the uncertainty.

Consider this scenario: A hurricane is approaching the East Coast. What if one U.S. government agency predicted the storm would make landfall as a category 1 to maybe category 2 storm, at worst, while another agency forecast the storm to reach the category 2, 3 or even 4 level? Imagine the widespread confusion that would ensue. How would anyone know if and how to prepare?

There’s a reason the National Hurricane Center closely works with local National Weather Service offices to coordinate hurricane and tropical storm information.

This needs to happen with NOAA and NASA and space weather.

The differences in the geomagnetic storm forecasts for the weekend probably reflect different roles and responsibilities in space weather at the two agencies. NOAA is the nation’s official source of alerts, watches and warnings about space weather and its impacts. NASA’s primary motivation for space weather forecasting is more specialized for “addressing the space weather needs of NASA’s robotic missions”.

Based on these different functions, it would appear NOAA’s information should be considered the most authorative and credible for impacts on Earth and NASA the go-to source for spacecraft. But while NOAA may well be the “official” source of information for our planet, the public and media take what NASA says seriously and NASA’s issuing Earth-based forecasts.

Citing NASA information, the very popular SpaceWeather.com website writes [bold text conveys my added emphasis] “According to a forecast track prepared by analysts at the [NASA] Goddard Space Weather Lab, the CME will hit Earth on July 14th around 10:20 UT (+/- 7 hours) and could spark strong geomagnetic storms.”

Contrast this with NOAA’s statement on its public Facebook page last night to expect [bold text conveys my added emphasis] “only minor geomagnetic storming here when the blast arrives likely Saturday, with few impacts noticeable to most people.”

Consider NOAA’s latest update, replete with acronyms and technical terms that non-specialists are likely to have trouble understanding:

The latest model run now indicates the CME associated with yesterday’s R3 (Strong) Radio Blackout event will impact the earth’s magnetic field around 9:00 a.m. EDT (1300 UTC) on Saturday, July 14. SWPC is forecasting category G1 (Minor) Geomagnetic Storm activity then, with a chance of G2 (Moderate) levels at times through July 15. The S1 (Minor) Solar Radiation Storm persists just above event threshold. Region 1520 has decayed in the past 12 hours, but is still potentially eruptive.

Based on preliminary heliospheric modeling carried out at NASA GSFC Space Weather Center, it is estimated that the CME may impact Earth, Messenger, Spitzer, MSL, Mars. Simulations indicate that the leading edge of the CME will reach Earth at about 2012-07-14T09:17Z (plus minus 7 hours). The roughly estimated expected range of the Kp maximum (Kp is a measure of geomagnetic disturbance levels ranging 0 - 9) is 6-8 (moderate to severe).

Why don’t these agencies prominently publish forecasts and explanations in plain English on their main websites for events attracting media attention?

This is a sorry state of affairs and I’d have to give NOAA and NASA very low marks for their space weather communication efforts.

But this does not absolve these Federal agencies from working together to provide clear, consistent information.

At some point in the future - especially with the solar cycle nearing its peak, it’s possible that a severe geomagnetic storm could threaten Earth with serious implications for satellite-based navigation and our power grid.

The stakes are high, and it’s unfortunate, at the moment, we cannot rely on Federal government to provide particularly helpful, harmonized information.

(Note: This morning, I contacted both NOAA and NASA to comment on these issues, and have not yet received responses except from NOAA to affirm they are the official source of space weather forecasts. I will publish anything more substantive I hear back from either agency.)

NASA scientists and the NOAA space weather prediction officials use different methods and models for their work. Estimating the level of geomagnetic storm activity that will result from a CME is difficult until the CME flows past NASA’s ACE spacecraft and the CME speed and orientation of the magnetic fields can be directly measured. In recent years, both NASA and NOAA have derived methods for estimating the initial CME speed just after it has lifted off the sun using images from NASA’s STEREO mission. Both groups also make assumptions about the likely orientation of the magnetic field when the CME impacts the Earth system. Different sets of variables, models, versions of models, and parameters are used. NOAA’s methods have more test and validation history and so properly make up an operational system. NASA’s job is to continually improve the state of the art in space weather understanding. While this explanation overly simplifies the different methods in place at NOAA and NASA, the aspects illustrate the major reasons one might anticipate variations in the projection information posted from event to event. It is interesting to note that since the initial alerts, additional data have become available and the two centers are converging to a consistent picture.

2) Why don’t NASA and NOAA coordinate on space weather forecasts to ensure a consistent message to the public?

NASA and NOAA and many other space weather professionals continually communicate, share data, and share perspectives during these space weather events. That said, the National Weather Service’s Space Weather Prediction Center is our nation’s official source of space weather alerts, watches and warnings. Those that depend on space weather information are always advised to consult those official predictions. Those that enjoy witnessing the progress of science and our nation’s ability to continuously improve on its prediction capabilities will also enjoy following the work of the NASA researchers as they enable the creation of our nation’s next generation prediction systems.

Jason is the Washington Post’s weather editor and Capital Weather Gang's chief meteorologist. He earned a master's degree in atmospheric science, and spent 10 years as a climate change science analyst for the U.S. government. He holds the Digital Seal of Approval from the National Weather Association.

Comments our editors find particularly useful or relevant are displayed in Top Comments, as are comments by users with these badges: . Replies to those posts appear here, as well as posts by staff writers.

To pause and restart automatic updates, click "Live" or "Paused". If paused, you'll be notified of the number of additional comments that have come in.

Comments our editors find particularly useful or relevant are displayed in Top Comments, as are comments by users with these badges: . Replies to those posts appear here, as well as posts by staff writers.

Spam

Offensive

Disagree

Off-Topic

Among the criteria for featured comments: likes by users, replies by users, previous history of valuable commenting, and selection by moderators.